Question

Car travels from 10mi to 30 mi in .40 hr. how fast are they going?

Answer 1

Answer:We will use our famous distance formula:

d = r x t.

Then, rearranging this formula, gives:

t = d/r

Now, t(for 1st 10 mi) = 10/30 = 1/3 hr.

And, t(for 2nd 10 mi) = 10/50 = 1/5 hr.

So, the total time = 1/3 + 1/5 hr.

Rearranging our distance formula again, gives: r = d/t

Now, r(average) = d(total)/t(total)

So, r(average) = 20/(1/3 + 1/5).

After simplifying, we get:

r(average) = 37.5 mi/hr.

Explanation:hope this helps!!!